Feedeeick k



(No Model.)

P. K. PITCH.

DYNAMO ELEOTRIG MACHINE. No. 293,441. Patented Feb. 12, 1884.

w' I i W 9551. ZOLWLC 532% -46 FREDERICK K. FITCH, OF NEIV YORK, X. Y.

DYNAMO-ELECTRlC MACi'llNt-I.

SPECIFICATION forming part of Letters Patent No. 293,441, dated February 12, l84.

Application filed May 16, 1883. (No model.)

To ct/YZ whom it may concern.-

Be it known that I, FREDERICK 1i. Frrorr, of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Dynamo-Electric Machines; and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification, in which Figure 1 is an end view of the armature without its coils. Fig. 2 is an edge view of one of the armature-rings. Fig. 3 is a longitudinal section of the armature on line 5c, and the polar fields of the inducing-magnet. Fig. 4 is an edge view of a portion of a ring made up of thinner plates. Fig. 5 is a detached view of one ring-segment about to be placed on the spider.

In an application filed by me January 17, 1883, I have shown and described a form of dynamo-electric machine involving certain principles of construction and arrangement.

The object of the present invention is to facilitate the construction of a machine of this character, and also to improve the con struction of certain parts applicable to other machines. To these ends my invention consists in the hereinafter described and claimed improve ments in the armature, field-magnets, and commutator or collector.

Instead of making each ring of the armature in two divisions, as in my former application, I form it of three or more equal segments, A, having the radially and laterally depressed grooves a for the winding of the generatingcoils Z). The drawings show the ring in three equal segments, A. One end of each segment is made with a tongue, 0, and the other with a corresponding groove, (1, so that the adjacent ends of any two segments will match to each other and form a tongueand-groovejoint. Through the overlap of the joint I insert one or more rivet-s or screws, 0, thus binding the segments firmly into a continuous ring. At each of the joints the seg ments A are made with a notch or recess, f, corresponding in width to the thickness of the spider-arms g, which project from the hub h.

At points to suit the desired position of the corresponding segments A of the respective rings, the outer edges of arms g are also notched, as shown at i, the width of notch corresponding to the thickness of the ring. By this construction the rings are locked firmly against independent movement in any direction whatever, while, if desired, any illdividual segment may be removed for repair of coils or rewinding by simply withdrawing the screws 0 and without disturbing the other rings.

Instead of making the poles of the inducingmagnets open-slotted to the full width of the rings, I now form them with the overhanging flanges k lapping the outer edges of the rings, and leaving narrow slits l at the middle. This not only adds more metal to the polar bodies, but causes 'the currents of air to circulate around the outer faces of the rings before cscaping.

The rings may be built up of sheet-iron stamped or cut to form, as shown at Fig. i, one or more pieces projecting to form the tongue-and-groovc joint 0 d, as before. The already described projections of the ring may be solid pieces attached in any suitable manner, or they,- too, may be built up of thin pieces of sheet-iron.

The commutator or collector consists of the longitudinal strips or segments Z, having at each end the notch in, enabling them to be set on the two non-conducting heads 21, which have each a bead or rib, 0, corresponding to the notches m. After being set on thus, rings 12 or hoops are driven onto the ends of the segments 2-, binding the whole cylinderstrongly in place. Hoops 1) may be of insulating material, or of metal with a non-conducting lining.

Instead of a tongueainl-groove joint, I can use the overlapping joint for the rings shown in my former application, the hercinbeforedescribed notches being used therewith to fit on the spider-arms.

I claim as my invention 1. In a dynamo-electric machine, the combination of an armature-ring composed of three or more segments connected together at their ends by overlapping joints and transverse rivets or screws, with a spider notched to receive said ring-segments, the latter being IOU also notched to receive the spider-arms, subit for seating on a spider, substantially as described.

4. The commutator composed of the longitudinalstrips Z, having the internal notches,

m, in combination with the non-conducting 20 heads a, having heads 0, and the inclosinghoops 12, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in presence of two Witnesses.

FREDERICK K. FITCH.

\Vitn esses:

T. J. PATTERSON, A. V. D. XVAT'rERsoN. 

